Microbes represent an invaluable source of novel genes and compounds that have the potential to be utilised in a range of industrial sectors. Scientific literature gives numerous accounts of microbes being the primary source of antibiotics, immunosuppressants, anticancer agents and cholesterol-lowering drugs, in addition to their use in environmental decontamination and in the production of food and cosmetics. A relatively unexplored group of microbes known as endophytes, which reside in the tissues of living plants, offer a particularly diverse source of novel compounds and genes that may provide important benefits to society, and in particular, agriculture.
Endophytes often form mutualistic relationships with their hosts, with the endophyte conferring increased fitness to the host, often through the production of defence compounds. At the same time, the host plant offers the benefits of a protected environment and nutriment to the endophyte.
Members of the Brachiaria-Urochloa species complex belong to the Poaceae family of grasses. Some species of Brachiaria-Urochloa are economically significant tropical forage grasses that have been released as commercial cultivars and include B. brizantha, B. decumbens, B. dictyoneura, B. humidicola, and B. ruziziensis, as well as corresponding interspecific and intraspecific hybrids.
Genetic diversity analysis based on internal transcribed spacer (ITS) nuclear ribosomal DNA sequence data indicates a strong affinity between Urochloa and Brachiaria, supporting morphological and anatomical studies that show a continuous gradation between these grass genera.
Seed-transmitted endophytic fungi have been observed in B. brizantha. These endophytes may play a role in protecting Brachiaria-Urochloa from fungal pathogens, such as Drechslera spp., which cause leaf spots.
There is a general lack of information and knowledge of the fungal endophytes of the Brachiaria-Urochloa species complex as well as of methods for the identification and characterization of novel endophytes and their deployment in Brachiaria-Urochloa plant improvement programs.
It is an objection of the present application to overcome, or at least alleviate, one or more of the difficulties or deficiencies associates with the prior art.